50 lines
1.8 KiB
Python
50 lines
1.8 KiB
Python
|
import numpy as np
|
||
|
|
with open('input11', 'r') as file:
|
||
|
|
seatmap = np.array([[c=='L' for c in line.strip()] for line in file.readlines()])
|
||
|
|
|
||
|
|
dir_slices = [np.s_[:-1,:], np.s_[:-1,:-1], np.s_[:,:-1], np.s_[1:,:-1], np.s_[1:,:], np.s_[1:,1:], np.s_[:,1:], np.s_[:-1,1:]]
|
||
|
|
|
||
|
|
def sim_step(seatmap, seatfilled):
|
||
|
|
neighbours = np.zeros_like(seatfilled, dtype=np.int8)
|
||
|
|
for i, dst in enumerate(dir_slices):
|
||
|
|
src = dir_slices[(i+4)%8]
|
||
|
|
neighbours[dst] += seatfilled[src]
|
||
|
|
output = seatfilled.copy()
|
||
|
|
output[np.logical_and(seatfilled==True, neighbours>=4)] = False
|
||
|
|
output[np.logical_and(seatfilled==False, np.logical_and(neighbours==0, seatmap==True))] = True
|
||
|
|
return output
|
||
|
|
|
||
|
|
occupied_seats = seatmap & False
|
||
|
|
while(True):
|
||
|
|
last_occ = occupied_seats.copy()
|
||
|
|
occupied_seats = sim_step(seatmap, occupied_seats)
|
||
|
|
if (occupied_seats == last_occ).all():
|
||
|
|
print(f'Part 1: Occupied seats = {occupied_seats.sum()}')
|
||
|
|
break
|
||
|
|
|
||
|
|
|
||
|
|
def sim_step_los(seatmap, seatfilled):
|
||
|
|
neighbours = np.zeros_like(seatfilled, dtype=np.int8)
|
||
|
|
for i, dst in enumerate(dir_slices):
|
||
|
|
src = dir_slices[(i+4)%8]
|
||
|
|
# Make floor propagate sight
|
||
|
|
fill2 = seatfilled.copy()
|
||
|
|
while(True):
|
||
|
|
fill2old = fill2.copy()
|
||
|
|
fill2[dst][~seatmap[dst]] |= fill2[src][~seatmap[dst]]
|
||
|
|
if (fill2 == fill2old).all():
|
||
|
|
break
|
||
|
|
neighbours[dst] += fill2[src]
|
||
|
|
output = seatfilled.copy()
|
||
|
|
output[np.logical_and(seatfilled==True, neighbours>=5)] = False
|
||
|
|
output[np.logical_and(seatfilled==False, np.logical_and(neighbours==0, seatmap==True))] = True
|
||
|
|
return output
|
||
|
|
|
||
|
|
occupied_seats = seatmap & False
|
||
|
|
while(True):
|
||
|
|
last_occ = occupied_seats.copy()
|
||
|
|
occupied_seats = sim_step_los(seatmap, occupied_seats)
|
||
|
|
if (occupied_seats == last_occ).all():
|
||
|
|
print(f'Part 2: Occupied seats = {occupied_seats.sum()}')
|
||
|
|
break
|